Clinical Trials

Completed Clinical Trials for Efzofitimod (ATYR1923)

ATYR1923-C-002: Investigational Trial of ATYR1923 for the Treatment of Pulmonary Sarcoidosis

In September 2021, we announced positive results from a Phase 1b/2a clinical trial evaluating efzofitimod (ATYR1923) in patients with pulmonary sarcoidosis.

Pulmonary sarcoidosis is an inflammatory disease of unknown cause, characterized by the formation of granulomas, clumps of inflammatory cells, in the lungs. If left untreated, this inflammation can lead to scarring (fibrosis) of the lung tissue resulting in permanent lung damage and in some cases death. Efzofitimod works by dampening immune responses in inflammatory disease states, with the goal of resolving inflammation and preventing progression to fibrosis. Efzofitimod’s mechanism of action overlaps with the cellular pathology observed in pulmonary sarcoidosis.

The Phase 1b/2a trial was a multiple-ascending dose, double-blind, placebo-controlled study evaluating efzofitimod in 37 patients with pulmonary sarcoidosis. The purpose of this study was to determine if efzofitimod was safe and tolerable in patients with pulmonary sarcoidosis who underwent a protocol-guided oral corticosteroid taper. This study was also designed to explore whether efzofitimod had the potential to reduce oral corticosteroid use, as well as the effects efzofitimod may have had on pulmonary sarcoidosis by measures of lung function, health-related quality of life assessments and disease biomarkers.

aTyr collaborated with the Foundation for Sarcoidosis Research (FSR), the nation’s leading nonprofit organization dedicated to finding a cure for sarcoidosis and improving care for sarcoidosis patients.
Data Release


ATYR1923-C-003: Investigational Trial of ATYR1923 for the Treatment of COVID-19 Related Severe Respiratory Complications

In the first quarter of 2021 we announced positive data from our Phase 2 clinical trial evaluating efzofitimod in patients with COVID-19 related severe respiratory complications. The trial was a randomized, double-blind, placebo-controlled study designed to investigate the safety and preliminary efficacy of efzofitimod as compared to placebo in 32 hospitalized COVID-19 patients with severe respiratory complications who did not require mechanical ventilation. Patients enrolled in the trial were randomized 1:1:1 to receive a single intravenous dose of either 1.0 or 3.0 mg/kg efzofitimod or placebo. Patients were followed for 60 days post treatment.
Data Release



In the second quarter of 2018 we announced positive data from our Phase 1 clinical trial of efzofitimod. This first-in-human, randomized, double-blind, placebo-controlled study was designed to investigate the safety, tolerability, immunogenicity and pharmacokinetics of intravenous efzofitimod in healthy volunteers. The Phase 1 study enrolled 36 healthy volunteers who were randomized to one of six cohorts and received a single infusion of intravenous efzofitimod or placebo. Doses of efzofitimod ranged from 0.03 mg/kg up to 5.0 mg/kg. The results indicate that the drug was generally well-tolerated at all dose levels tested, with no significant adverse events or induction of anti-drug antibodies observed following efzofitimod dosing or throughout the one-month follow-up period.

The pharmacokinetics (PK) of efzofitimod following single-dose administration were linear across the evaluated dose range. Higher efzofitimod doses yielded sustained serum concentrations through the end of the one-month follow-up period that were above the predicted therapeutic threshold, supporting the potential for a once-monthly dosing regimen.
Data Release



Kyorin Pharmaceutical, our partner for development and commercialization of efzofitimod for ILD in Japan, conducted a Phase 1 clinical trial of efzofitimod, which investigated the safety, PK and immunogenicity of efzofitimod (known as KRP-R120 in Japan) in 32 healthy Japanese volunteers. In this study, efzofitimod was observed to be generally safe and well-tolerated with no drug-related serious adverse events and PK findings were consistent with previous studies of efzofitimod.

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